Reverse motion alarm

ABSTRACT

A reverse motion alarm, which may be mounted anywhere on a vehicle or machine in proximity to a rotating or translating member whose direction of rotation changes with the direction of motion of the vehicle or machine, may include a friction wheel driven by the rotating or translating member, a shaft-mounted overrunning clutch which transmits rotation in one direction only, a cam driven through the clutch and a spring biased clapper mechanism actuated by the cam which rings a bell upon reverse movement of the vehicle or machine.

United States Patent Peterson 1 1 Feb. 26, 1974 [54] REVERSE MOTIONALARM 2,979,020 4/1961 Von Radios 1. 116/60 72,092 1 l 1 1 1mm EdwmPeterson, 3109 Bogus 3,339 423 61132; $33??? H2128 B351" -i B0158, Idaho33702 3,043,142 8/1962 Warn 116/60 [22] Filed: Apr. 2, 1973 PrimaryExaminerLouis J. Capozi [21] Appl No; 346,976 Attorney, Agent, or FirmJ.Gibson Semmes [52] US. Cl. 116/60, 116/158 [57] ABSTRACT Int. Cl. Areverse motion alarm which ma b y e mounted any- [58] held of Search 116/35 where on a vehicle or machine in proximity to a rotat- 116/61 ingor translating member whose direction of rotation 180/106 340/392changes with the direction of motion of the vehicle or machine, mayinclude a friction wheel driven by the [56] References cued rotating ortranslating member, a shaft-mounted over- UNITED STATES PATENTS runningclutch which transmits rotation in one direc- 773,565 1 H1904 Hakes116/57 tion only, a cam driven through the clutch and a 1,327,993 1/1920Goldb1att.... 116/56 spring biased clapper mechanism actuated by the cam2,244,431 6/194l Piccardl 1 16/167 X which rings a bell upon reversemovement of the vehi- 2,900,948 8/1959 Krynak 116/60 cle or machine2,915,036 12/1959 Bookwalter 1 116/56 X 2,957,443 10/1960 Carlisle116/57 X 4 Claims, 2 Drawing Figures REVERSE MOTION ALARM FIELD OF THEINVENTION Numerous devices are known which will provide an audiblewarning signal when a vehicle or machine is set in motion. Generally,the signal is made only in the reverse direction since the operator thenhas a more restricted view of the objects and persons in the path of thevehicle or machine. In the applicants U.S. Pat. No. 3,629,819 isdisclosed such a device comprising an electronic circuit which sounds analarm when the vehicle is in reverse motion. The present invention is ofsimple mechanical design and requires no knowledge of electronics forits complete installation.

DESCRIPTION OF THE PRIOR ART In the past there have been numerousmechanical devices suited for providing alarms during vehicle motion;however, none of the, known devices anticipate or suggest the simple,novel arrangement of parts of this invention. U.S. Pat. No. 2,900,948 toKrynak (Class 1 l6, Subclass 60) shows a warning signal for a rail carin which a wheel is driven by friction from the rail car wheel, therebyrotating a shaft and clapper mechanism which rings a bell regardless ofthe direction of motion of the vehicle. This device includes a gravityactuated clapper mechanism, compared to the applicants uniquecam-driven, spring-biased system. U.S. Pat. No. 2,915,036 to Bookwalter(Class 116, Subclass 35) shows a signal device in which an impact memberis permitted to roll into contact with a bell upon rotation of the guidetube carrying the impact member in one direction but is prevented fromstriking the bell upon rotation of the guide tube in the oppositedirection. This device must be mounted to the hub of the vehicle wheelwhere it interferes with vehicle tire maintenance, is subject to damagefrom impact by flying objects or objects close to the vehicle and toclogging or blocking of the guide tube due to mud, grease and grime. Thepresent device is suited for mounting in the protected area of the driveshaft and thus is not susceptible to such damage, and, due to theunique, open geometry of the elements of the invention, tends to beselfcleaning. U.S. Pat. No. 2,957,443 to Carlisle (Class 116, Subclass56) shows a reverse movement alarm mounted around the drive shaft of thevehicle which includes a ratcheting mechanism which rings a bell in onedirection but not in the other. The present device represents animprovement over this patented apparatus in that it mounts in a simplefashion directly to the frame or other structural member of the vehiclerather than around the drive shaft which would appear to requiredisassembly of the drive train for installation of the warning device.

U.S. Pat. No. 2,979,020 to Von Radics shows an alarm system whichincludes a drive input from the vehicle transmission, an overrunningclutch, a flexible draft shaft leading to the bell ringing mechanism anda centrifugally actuated bell ringer. This device requires a rathercomplex mounting arrangement on the vehicle in contrast to theapplicants simple, universal bolt-on arrangement; and has a clappermechanism quite different from and inferior to the within uniquelycamdriven, spring-biased system. U.S. Pat. No. 3,039,423 to Warn shows asafety alarm wherein a wheelmounted, counter-balance activated camsystem moves and releases the spring-biased bell ringing hammer.

This system is susceptible to freezing in-place due to mud, grease andgrime and does not show the applicants unique bell ringing hammer whichis driven into contact with the bell by the biasing spring to producelouder warning sounds than possible with the flexibly mounted arm of thepatent. U.S. Pat. No. 3,072,092 to Krynak shows another warning systemin which a friction wheel drives a shaft having a cam element mountedthereon which actuates a bell-ringing mechanism. The invention withinrepresents an improvement over this apparatus in that the simpleoverrunning clutch replaces the complex spring system of the patenteddevice.

SUMMARY OF THE INVENTION An object of this invention is to eliminatesuch above-noted problems as have been encountered with prior artdevices by providing a mechanically simple reverse motion alarm which iseasy to install and maintain, does not interfere with the function ormaintenance of any other component of the vehicle or machine and may beinstalled in a variety of locations near a rotating or linearly movingmember of the vehicle or machine whose direction of movement changeswith the vehicles or machines direction. To these ends there areprovided a mounting frame of simple geometry having a shaft mountedthereon on suitable bearings. Also affixed to the frame are one or morebellringing hammers, spring biased into close proximity to an adjacentbell, which may be mounted on the frame or on the shaft. Located on theshaft in proximity to the hammer is a cam of suitable shape having oneor more lobes which will engage the hammer as the cam rotates with theshaft; move the hammer against the action of its spring; and release thehammer to cause it to strike the bell under the return action of thespring. The hammer then returns to a neutral position awaiting the nextcontact by the cam. Also located on the shaft is an overrunning clutchof known variety which will transmit motion to the shaft in onedirection only. Mounted on the input side of the overrunning clutch is awheel and tire assembly or similar apparatus which is driven by themovement of the rotating or linearly moving member of the vehicle. Whenthe vehicle or machine moves in the reverse direction, the clutchtransmits motion to the cam, which moves the hammer and releases it,causing the bell to ring.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 shows a side elevation view,partially cut-away and partially in section, of the invention.

FIG. 2 shows a cut-away front view of the invention, taken along line2-2 in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT There follows a description ofthe preferred embodiment of the invention, reference being made to thefigures of the drawing wherein like reference numerals designate likeelements of structure in the two figures.

Attached to vehicle or machine frame 10 or other structural member isthe mounting frame 12 of the invention, having a suitable connectingfastener 14. Frame 12 may include an aperture 16 in which may be mountedbearing assembly 18. Mounted within bearing assembly 18 is shaft 20rotatable freely therein. Frame 12 may further include apertures 22 and24 having hammer pivot posts 26 and 28 mounted therein. Pivot posts 26and 28 may include threaded ends 30 and 32 for receiving nuts 34 and 36;and integral collar segments 38 and 40 for abutting frame 12 at one end.The other ends of collars 38 and 40 may abut bushings 42 and 44, orother sleeve-type bearing, on which may be mounted bell-ringing hammers46 and 48. Hammer return springs 50 and 52 may also be mounted on pivotposts 26 and 28 outwardly of the hammers, with one end of each springsecured to its respective pivot post. The other end of each returnspring may be affixed to cam follower pins 54 and 56 mounted in andextending through hammers 46 and 48. By adjusting the tension of springs50 and 52, the force with which the hammers strike the bell and, hence,the sound level of the bell may be varied. Slots 74 and 76 are providedfor tension adjustment.

Attached to shaft is hammer actuating cam 58, located so as to permitthe cam to contact and movecam follower pins 54 and 56 as cam 58 rotateswith shaft 20. In the preferred embodiment, bell 60 is mounted on andmoves with shaft 20, which tends to shake out dirt, grease and grimewhich would otherwise accumulate within the bell and could interferewith the operation of the hammers and muffle the sound of the bell. Ofcourse, the bell may alternately be mounted on frame 12 or otherwise asmay be convenient and still permit the hammers to strike it when shaft20 is rotating. Also mounted on shaft 20 is overrunning clutch assembly62 on the input side of which may be mounted a wheel 64 having a tire 66mounted thereon. Locknut 68 secures the assembly to shaft 20. Tire 66,or other suitable surface, may be placed in contact with a rotating orlinearly moving member of the vehicle or machine to actuate the assemblywhen the vehicle or machine moves in reverse.

FIG. 2 shows a view taken along line 22 of FIG. 1, and indicating moreclearly the geometry of the preferred embodiment. Hammers 46 and 48 maybe made from rigid metal plate stock from essentially rectangularblanksfrom which one side, one corner and a portion of another side areremoved to form diagonal sides 70 and 72, which permit the hammers torotate about pivot posts 26 and 28 without contacting shaft 20. Thispermits very compact arrangement of the parts. The hammers may also beinstalled in thereverse of their illustrated positions, i.e., turnedover facing oppositely, to provide the flexibility of actuation uponmovement of shaft 20 in the opposite direction to that shown. Of course,additional hammers could be added as desired to provide more rings perrevolution of cam 58. Hammer actuating cam 58 may have one or aplurality of actuating lobes, such as the three lobes shown, as desiredto produce more or less rings per revolution.

Other modifications which may occur to those in the art and which arewithin the spirit of the invention might include the direct mounting ofthe drive wheel upon the shaft so that the device will be actuatedregardless of the direction of motion of the vehicle. The inventiveapparatus may also be used as a warning device on a conveyor belt, forthe fast return of the car riage on a large lathe or milling machine, onthe drive pulleys of overhead cranes, on the raising mechanism of a dumptruck and similar applications.

Having described my invention in such detail as to enable one skilled inthe art to make and use it, I claim:

L'A reverse motion alarm for an apparatus having a moving member whosedirection of movement changes with the direction of movement of theapparatus, comprising:

A. a frame member adapted for mounting upon the apparatus;

B. bearing means mounted in the frame member;

C. a shaft mounted in the bearing means for rotation therein;

D. a cam mounted on the shaft, the cam having at least one lobe;

E. means connected to the shaft for producing a rotating motion in theshaft only in a reverse direction of movement of the moving member;

F. means attached to the frame member for actuating a sound producingmeans in response to contact by the at least one cam lobe; and

G. means for producing an alarm sound in response to the actuatingmeans.

2. The apparatus of claim 1, wherein the means for producing a rotatingmotion comprises:

E-l. a wheel adapted to be driven by the moving member; and

E-2. an overrunning clutch mounting the wheel to the shaft fortransmitting the rotation of the wheel to the shaft.

3. The apparatus of claim I, wherein the alarm producing means comprisesa bell mounted on the shaft for rotation therewith.

4. The apparatus of claim 1, wherein the means for actuating a soundproducing means comprises:

F-l. a pivot post mounted to the frame member;

F-2. at least one alarm actuating hammer mounted on the pivot post forrotation thereabout;

F-3. spring means for biasing the hammer into contact with the alarmsound producing means; and

F-4. cam follower pin means mounted on the hammer for coaction with thecam lobe, whereby the hammer is moved away from the sound producingmeans as the cam lobe rotates and be released to actuate the soundproducing means under the action of the spring means.

1. A reverse motion alarm for an apparatus having a moving member whosedirection of movement changes with the direction of movement of theapparatus, comprising: A. a frame member adapted for mounting upon theapparatus; B. bearing means mounted in the frame member; C. a shaftmounted in the bearing means for rotation therein; D. a cam mounted onthe shaft, the cam having at least one lobe; E. means connected to theshaft for producing a rotating motion in the shaft only in a reversedirection of movement of the moving member; F. means attached to theframe member for actuatIng a sound producing means in response tocontact by the at least one cam lobe; and G. means for producing analarm sound in response to the actuating means.
 2. The apparatus ofclaim 1, wherein the means for producing a rotating motion comprises:E-1. a wheel adapted to be driven by the moving member; and E-2. anoverrunning clutch mounting the wheel to the shaft for transmitting therotation of the wheel to the shaft.
 3. The apparatus of claim 1, whereinthe alarm producing means comprises a bell mounted on the shaft forrotation therewith.
 4. The apparatus of claim 1, wherein the means foractuating a sound producing means comprises: F-1. a pivot post mountedto the frame member; F-2. at least one alarm actuating hammer mounted onthe pivot post for rotation thereabout; F-3. spring means for biasingthe hammer into contact with the alarm sound producing means; and F-4.cam follower pin means mounted on the hammer for coaction with the camlobe, whereby the hammer is moved away from the sound producing means asthe cam lobe rotates and be released to actuate the sound producingmeans under the action of the spring means.